Ussuritidae

Ussuritidae Temporal range: Triassic
Fossil of Monophyllites sphaerophyllus from Bosnia, on display at Galerie de paléontologie et d'anatomie comparée in Paris
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	Ammonoidea
Order:	Ammonitida
Suborder:	Phylloceratina
Family:	Ussuritidae

Ussuritidae are ancestral, Triassic, Phylloceratina characterized by generally smooth, discoidal, evolute shells with rounded venters and little or no ornamentation and by sutures with primitive monophyllitic saddles with a single terminal branch or leaflet.

The Ussuritidae are most likely derived from the Dieneroceratidae and give rise to the Discophyllitidae. Seven genera are included:

Genera are distinguished on the basis of shell morphology and characteristics of the suture.

Ussuritidae are also known as the Monophyllitidae, a junior synonym. Palaeophyllitidae, for Palaeophyllites, is sometimes found in the literature.

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